Brainstorming out loud, to see if anything catches:
I've touched on this before, but looking to expand on it. Apologies for Ne'ing out loud, dear Ni'ers:
Ni dom vs Ne aux ... Fi dom vs Fe aux. Both of us have the opposite function of each other's dominant in the auxiliary position, the "problem-solver" position. To me, this means we tend to look at that function as our salvation to a certain extent, and this makes it challenging for us to see the downsides of the function overall. We tend to feel positive when engaging it. We don't see the problems it creates as clearly, because although it is essential for us to lean on that function, the very act of leaning on it means we trust it more.
(And yes, I also see the irony of Ne'ing right here in this post. No need to point it out Mane!)
That said, Fe is there working in the problem-solving role to discern and adjust to the needs of others, even to the point of getting the feelings of others mixed up with one's own. (Note to self: Could it be that OA's grumpy tone was just 'catchy'?) Other characteristics that grow out of Fe are the values of being polite, considerate and socially appropriate in one's behavior. It seems to me that most of what the INFJ's are saying here falls within that catchment area, that they need this protocol of interaction to be established before they can even entertain to engage in a more trust-oriented, two-way relationship.
Additionally, Fe'ers tend to need to feel appreciated. They are sensitive to what others think of them. They are easily hurt within that purview. When someone falls out of the bounds of good behaviour, it's natural to turn to the problem-solver to 'bite back', deploying it with intention and an element of self-protection. It's about ... connecting and disconnecting, it connects warmly and faithfully, and disconnects readily when negativity is encountered.
So, speaking broadly in terms of the N function, Ni-dom sees more readily the "dark side" of Ne in the aux, the problem with chasing the bunny down every rabbit hole, and sees that each hole does not have an equal probability of being worth searching. Ne wastes time, is inefficient and annoying. This ties into Z's metaphor of taking each spaghetti-string-bikini, size 2 to 26, into the dressing room, and how aggravating that is to watch. The problem for INFP's is that if we don't investigate each rabbit hole at least a little bit, we don't have an internal radar built-in to hone in on which has a more likely probability of being useful. We just think using it is useful, because we need to explore, out loud, to see how in the "real world" we can realistically enact our values.
Next, speaking broadly in terms of the F function, Fi-dom sees more readily the "dark side" of Fe in the aux, how it shuts down people before giving them a chance to speak, how it contains elements of what seems to look like bullying and prejudice. How it judges quickly and readily, and the inherent concerns of that. This ties into my metaphor on needing each voice to comprise a part of my knowledge-web, how hearing each voice ensures equality to create a web of strength and utility. The problem for INFJ's, if they don't use Fe at all in the 'negative' position, they risk having their boundaries violated again and again. Using it keeps them safe from those who would exploit the social contract.
More to come ... eta, I just made myself lost lol ... will add more as it arrives? If it arrives? I know I was going somewhere ...